What are the classifications of boilers?

First, by purpose:

1. Power station boiler: used for power generation, mostly large-capacity, high-parameter boiler, fire chamber combustion, high efficiency, and the export working medium is superheated steam.
2. Industrial boilers: used for industrial production and heating, most of which are low-pressure, low-temperature, small-capacity boilers, which are mostly burned by fire beds, with low thermal efficiency. Exports, working fluids are called steam boilers, and the working medium is hot water. It is called a hot water boiler.
3. Marine boiler:
4. Locomotive boiler:
5. Steam injection boiler: used for oil injection of heavy oil in oil field, the export working medium is generally high pressure wet steam.

Second, by structure:

1. Fire tube boiler: The flue gas flows through the fire tube. It is generally a small-capacity, low-parameter boiler with low thermal efficiency, but the structure is simple, the water quality requirements are low, and the operation and maintenance are convenient.
2. Water tube boiler: The steam water flows through the tube and can be made into a small capacity, low-parameter boiler, or a large-capacity, high-parameter boiler. Power station boilers are generally water tube boilers with high thermal efficiency, but also have high requirements for water quality and operating level.

Third, classified by cycle

Natural circulation drum boiler
2. Multiple forced circulation boiler
3. Low rate circulating boiler
4. Once-through boiler
5. Compound circulation boiler

Fourth, according to the boiler outlet working pressure classification

1. Low pressure boiler: the general pressure is less than 1.275MPa
2. Medium pressure boiler: the general pressure is 3.825MPa
3. High pressure boiler: the general pressure is 9.8MPa
4. Ultra-high pressure boiler: the general pressure is 13.73MPa
5. Subcritical pressure boiler: general pressure is 16.67MPa 6. Supercritical pressure boiler: general pressure is 22.13MPa

Fifth, classified by combustion method

1. Fire bed combustion boiler: mainly used in industrial boilers, including fixed grate furnaces, reciprocating grate furnaces, etc.
2. Fire chamber burning boiler: mainly used in power station boilers, boilers burning liquid fuel, gaseous fuel and pulverized coal are fire chamber burning boilers
3. Boiling furnace: The air flow rate sent to the grate is high, so that large particles of coal are tumbling in the boiling bed above the grate, and small particles of coal are rising with the air and burning.

Sixth, classified by fuel or energy used

1. Solid fuel boiler: burning solid fuel such as coal;
2. Liquid fuel boiler: burning liquid fuel such as heavy oil;
3. Gas fuel boilers: burning gaseous fuels such as natural gas;

Seventh, classified by slag discharge method

1. Solid waste slag boiler
2. Liquid slag boiler

Eight, according to the furnace flue gas pressure

1. Negative pressure boiler: the furnace pressure maintains negative pressure, and there are sending and drafting fans, which are the main types of coal-fired boilers;
2. Micro-positive pressure boiler: the surface pressure of the furnace is 2-5KPa, no need for induced draft fan, easy to low-oxygen combustion;

Ninth, drum layout classification

1. Single drum
2. Double drum

Tenth, waste heat boiler: use waste heat from metallurgical, petrochemical and other industries as heat source;

Eleventh, atomic energy boiler: a steam generator that uses thermal energy released by a nuclear reactor as a heat source;

Twelfth, waste heat boiler: a boiler that uses waste such as garbage, bark, and waste liquid as fuel;

Thirteenth, other energy boilers: steam generators or water heaters that use geothermal, solar energy and other energy sources.

Class A boiler: rated working pressure (gauge pressure, the same below) P ≥ 3.8 MPa boiler, including:
1. Ultra-supercritical boiler: B≥27.0MPa or rated outlet temperature ≥590°C;
2. Supercritical boiler: 22.1MPa≤P<27.0MPa;
3. Subcritical boiler: 16.7MPa ≤ P < 22.1MPa;
4. Ultra-high pressure boiler: 13.7MPa≤P<16.7MPa;
5. High pressure boiler: 9.8MPa ≤ P < 13.7MPa;
6. Secondary high pressure boiler: 5.4MPa ≤ P < 9.8MPa;
7. Medium pressure boiler: 3.8MPa ≤ P < 5.4MPa.
Class B boiler：
1. Steam boiler: 0.8MPa<P<3.8MPa or rated evaporation >1.0t/h;
2. Hot water boiler: rated outlet water temperature ≥ 120 ° C or rated thermal power > 4.2 MW;
3. Organic heat carrier boiler:
(1) a boiler using a gas phase organic heat carrier;
(2) Liquid phase organic heat carrier boiler: rated thermal power > 4.2 MW;
Class C boiler： the following boilers except for the D-class boiler:
1. Steam boiler: a steam boiler with a rated working pressure ≤ 0.8 MPa and a rated evaporation ≤ 1.0 t/h;
2. Hot water boiler: rated outlet water temperature <120 ° C and rated thermal power ≤ 4.2 MW;
3. Liquid phase organic heat carrier boiler: rated thermal power ≤ 4.2MW.
Class D boiler:
1. Steam boiler: when designing the normal water level, the water volume is ≤ 50L and the rated working pressure is <0.8MPa;
2. Soda-water dual-purpose boiler: Boiler with rated working pressure ≤0.04MPa and rated evaporation ≤0.5t/h; E. Only hot water boiler pressurized with tap water, and the outlet water temperature is ≤95°C.

Fifteen, free name classification:

Coal-fired boilers, hot water boilers, oil-fired boilers, steam boilers, electric boilers, environmentally friendly boilers, special boilers, gas boilers, water tube boilers, heat transfer oil boilers, special boilers, dual fuel boiler, waste heat boilers, atmospheric boilers, electric boilers, Industrial boilers, hot air boilers, pressure boilers, vacuum boilers, chain boilers, domestic boilers, biogas boilers, heating boilers, tea bath boilers, power station boilers, straw gasifiers, incinerators, coal-water slurry boilers, gas generators, Organic heat carrier boiler, circulating fluidized bed boiler
Note: Our commonly mentioned boilers refer to industrial boilers, steam boilers, hot water boilers and organic heat carrier boilers.

Note: Our often mentioned boiler refers to an industrial boiler, steam boiler, hot water boiler, And organic heat carrier boilers.

Usage and characteristics of roller turning conveyor

The roller turning conveyor is mainly composed of a driving roller, a frame, a support, a driving part and the like, and is suitable for conveying articles with a flat bottom. It is divided into powered, unpowered, and electric drums from the driving form, and is divided into horizontal conveying, inclined conveying and turning conveying according to the layout form.
The inner width of the roller conveyor is specified by the customer and can be produced according to customer requirements. The standard turning inner radius of the turning line is 300, 600, 900, 1200mm, etc., and other special specifications can also be adopted according to customer requirements. Straight rollers have roller diameters of 38, 50, 60, 76, 89mm, etc. The taper of the turning drum will be designed according to the weight, shape and linear speed of the conveyed object.
Frame material: carbon steel spray, stainless steel, aluminum profile.
Power mode: drive by reduction motor, drive by electric drum, etc.
Transmission mode: single sprocket, double sprocket, O-belt, flat friction transmission belt, timing belt, etc.
Speed regulation mode: variable frequency speed regulation, stepless speed change, etc.
The roller turning conveyors are easy to connect and filter, and multiple roller lines and other conveying equipment or special machines can be used to form a complex logistics conveying system and a shunting and combining system to complete various process needs. The structure is simple, high reliability, easy to use and maintain. The power roller line needs to consider the tensile strength of the chain, and the longest single line length generally does not exceed 10 meters.
In gravity roller conveyor applications, the use of open or steel shielding covers can avoid increasing the friction of the bearings. Although the application temperature of the bearing can be as high as 170 ° C, the temperature of the steel shielded bearing cannot exceed 100 ° C, because the shielding cover will be deformed. In higher temperature applications, the interval between conveyor belt loads should be increased and moved quickly to reduce the absorption of heat from the drum.
The load capacity of the roller is determined by the bearing load capacity and the width of the roller. The basic bearing load capacity is determined by empirical formulas and experimental tests. Rated with a narrow width conveyor. If the width increases, the load capacity of the roller will decrease due to the deformation of the shaft.
There are three types of assembly methods: direct pressing type, curling type and forming type. The roller assembly on the skeleton track can be higher or lower than the skeleton. If the roller is lower than the skeleton track, the skeleton track can be used as a guide rail without installing a safety fence. If a wider load is used, it cannot be used because the load will interfere with the skeleton.
Relatively, the roller is higher than the frame, and a safety fence is installed, which is more flexible in application. The most common skeleton types are channel steel, L-shaped steel or flat plate. Divided by the forming method, it can be divided into bending forming and structural steel. The structural steel has a heavier weight and better strength, and is used for heavy loads. Usually, the same steel is used on both sides of the conveyor and welded by the supporting beam Or bolted. For some specific applications, the types of the two sides of the skeleton are not the same.

Application of Handheld Mobile Terminal In Highway Inspection Management

In order to promote the standardization of the operation and management of the expressway service area, standardize the work procedures of the service area managers, and achieve the goal of "complete facilities, beautiful environment, and standardized service" in the service area, Ruggedmobi has developed a handheld mobile terminal to inspect the expressway Management solutions.
Freeway inspection management system. On the one hand, during the inspection process, the handheld mobile terminal performs field information input and photographing of inspection points, scoring, and existing problems, and transmits them to the management system in real time. On the other hand, the system administrator can formulate inspection tasks in the system, automatically remind the inspection, and provide a standardized inspection result record form for inspection personnel.
The inspection personnel fill in the form directly based on the inspection results, and automatically generate the daily routine inspection and maintenance form. In the future, the daily inspection and monthly inspection can be summarized, analyzed and exported.

(A) Expressway service area management system
1. Authority management ----- Information management, role management and authority allocation for inspection personnel.
2. Inspection task management ------ It mainly includes manual formulation and automatic generation of inspection tasks, task allocation, inspection and completion inspection.
3. Data exchange with handheld mobile terminal ----- Equipment inspection standards, facility data, personnel conditions, task information and other information are downloaded to the handheld mobile terminal, and the handheld mobile terminal inspection results are transmitted back to the system.
4. Comprehensive query of inspection results ------- Inquiry of inspection in place rate to supervise inspection quality.
5, basic data maintenance ----- Mainly to achieve the maintenance of basic data required by the system.
(B) Handheld mobile terminal patrol operation system
1. Basic data reception --- Information such as equipment inspection standards, facility data, personnel conditions, and mission information are downloaded from the application server to the handheld mobile terminal.
2. Prompt for inspection task ------ It can prompt the relevant data of inspection task, and can query the basic information of the inspection object and the current record information of the inspection object.
3. Facility inspection function ------ By handheld mobile terminal identification of radio frequency tag inspection points, the inspection process can be accurately recorded.
4.Return inspection results
(C) Handheld mobile terminal (M68) and radio frequency electronic tag
1. The Ruggedmobi is a high-industrial-grade handheld mobile terminal M68, which integrates high-frequency RFID tag reading and writing and GPRS wireless transmission functions, to meet the requirements of the equipment under harsh environments and operating conditions.

2. The radio frequency electronic tag uses two types of high frequency ISO14443A protocol: ordinary tag and anti-metal tag. Form of label encapsulation: attached label and tag label.
(D) Inspection process
1. Log in the account of the inspector, download the current inspection task assigned by the background management system, and automatically generate the inspection result record form.
2. According to the inspection task, carry out actions on the inspection points located by radio frequency tags and take photos to record. The inspection results are transmitted back to the background system in real time through GPRS.
3. The handheld mobile terminal checks whether the current inspection task has been completed. If there is any omission, the handheld mobile terminal will prompt.
4. The hand-held mobile terminal patrol operation system synthesizes the scoring results of each inspection point, evaluates the comprehensive score, and transmits it back to the host. The inspection is completed.
The solution of the handheld mobile terminal in the highway inspection management basically eliminates the phenomenon that the inspection personnel and the inspected objects cannot be scientifically and accurately evaluated and monitored, which effectively ensures that the inspected facilities in the highway service area are always in a good state.

Under what circumstances will the uhf rfid tag fail?

  Uhf rfid tag is very common in life. RFID is generally similar to barcode scanning. If the RFID electronic tag fails, it is impossible to scan and apply. Then what kind of situation can prevent the RFID electronic anti-counterfeit tag from malfunctioning?

          To prevent malfunction, first of all you need to know that there are several cases RFID tag failure

         The first case is the damage of the label, because there are chips inside the RFID electronic tag. Once the chip is pressed by external force or touched by static electricity, it may cause failure. There is also the destruction of the RFID signal antenna, which will also cause failure. Generally speaking, RFID electronic tags must not be damaged by compression and tear. High-quality RFID electronic tags are generally packed in plastic cards, which can avoid damage by external forces. .

          In the second case, the tag is not damaged. Generally, RFID electronic tags cannot pass through metal because metal can shield signals. rfid also difficult to penetrate water, since water can absorb waves to occur when sensing distance limit. So pay attention to whether these substances are present in blocked when in use

           The third situation is far read distance, practical application of high-frequency RFID tag, the electronic tag important considerations bonding position since relatively large size of the label, the RFID tag is attached directly to the metal surface or The location close to the metal device is directly integrated on the battery aluminum alloy stamped case because of space problems. Therefore, during the identification process, the RFID electronic tag is easily susceptible to the eddy current interference of the battery aluminum alloy stamped case, resulting in an RFID tag. The actual valid read greatly shorten the distance, or no response is altogether, resulting in a failure to read. This interference problem occurs more often, so some measures need to be taken to prevent it.

 

 

How to solve the problem of weak skid steer bucket speed

More than 90% of the construction actions of the excavator are inseparable from the bucket. Simply speaking, the more powerful the bucket action, the more active it will be, and the easier the operator will operate it. Stop and repair as soon as possible.

Failure phenomenon and cause
Failure phenomenon: When the skid steer bucket is working, both the single-action and compound-action buckets are very slow, the soil is weak, and the bucket will automatically lower the pressure when it is retracted.
The reasons that can cause this failure are:
1. The secondary pilot pressure of the bucket is low. The secondary pressure of the bucket is the pilot pressure between the pilot control valve and the main valve. When the pilot control valve core is worn and stuck, it will cause the secondary pilot pressure to be low.
2. Bucket spool is stuck and worn. Abrasion between the bucket main valve and the spool will cause the pressure oil to leak internally, reducing the main pressure. Stuck in the half-open position will reduce the pressure oil flow and make the action slow.
3. The skid steer bucket overload valve is faulty. The valve body and valve core of the bucket overload valve are worn, making the overload valve unable to maintain the main pressure, and it will leak from the worn part. The reason that the seal ring of the overload valve is damaged is the same as above.
4. The bucket oil cylinder leaks; the piston oil seal inside the bucket oil cylinder is damaged, or the inner wall of the bucket oil cylinder is strained, which causes oil in the large and small cavities of the oil cylinder to cause internal leakage.
Troubleshooting
1. First use a pressure gauge to test the pilot pressure of the bucket valve core and the secondary pressure from the right control valve to the rear pump regulator. If the measured value is within the normal range, the secondary pilot pressure and bucket valve core are switched normally. .
2. Then use a pressure gauge to detect the main pump pressure when the bucket is overloaded. The pressure is lower than the normal overflow pressure. Because other operating pressures and speeds are normal, the problem may be in the bucket cylinder, bucket spool or overload relief valve. on.
Because the principle of the bucket relief valve is the same as that of other overload valves, engineers can swap the overload valves and test again. If the fault persists, the failure of the bucket overload valve is eliminated.
3. Pull out the skid steer bucket valve core for inspection. The surface is smooth and free of wear. If the clearance is good, there is no problem.
After the above measurements and inspections, the last thing to doubt is the problem of the bucket cylinder itself. However, because disassembling the bucket cylinder is very time-consuming and labor-intensive, and there are no special tools, do not rashly disassemble the cylinder, you can open the hydraulic tank for inspection. If the inspection reveals impurities in the return oil filter, which are similar to the debris of the oil seal, it can be further determined that the problem is the bucket cylinder itself.
The bucket oil cylinder was disassembled and inspected to find that the piston oil seal in the bucket oil cylinder was damaged, resulting in internal leakage of the hydraulic oil, which made the bucket slow and weak. After replacing the bucket oil seal of the bucket cylinder and testing the machine, the failure can be resolved, and the pressure and speed will return to the original state.
to sum up
The skid steer bucket is in direct contact with the external environment and the work object, so its fatigue and work intensity are very large. When encountering hard objects, do not use violent manipulation to avoid damage to the oil cylinder.
In addition, the usual inspection, maintenance, and maintenance work can not be lazy, especially the wearing parts such as oil seals. As time goes by, the probability of aging and breaking of the oil seals is very high. It is timely found and replaced in time to ensure that no failure occurs.